The Usage of Taguchi Method in RCC Mix Optimization with Waste Materials Incorporations

Employing different waste materials in roller compacted concrete (RCC) mixtures has fascinated investigators recently. The main interception of utilizing wastes in concrete is its engineering properties loss. As a result, using additives has been suggested to modify mechanical properties of mixes efficiently and economically. In present research, waste crumb rubber has been used for fabricating specimens and the influence of nano-silica and fly ash incorporation was assessed. Design of experiments was programed using Taguchi method and mix design was optimized accordingly. A 40 % to 70% fly ash content (by the weight of cement and replacement), 0 to 30% crumb rubber content (by the weight of fine aggregates and replacement) and 0 to 3% nano-silica content (by the weight of cement and replacement) were incorporated in the RCC mixtures. Moreover, L16 orthogonal array with a mixed-level design and signal-to-noise (S/N) of larger is the better was used for design of experiments. The Taguchi method is a proper way for mix optimization and determining precise percent of components in mix design. The main objective is RCC strength optimization based on RCC structural limitations. It is noteworthy that crumb rubber incorporation in concrete precedes mechanical loss of mixture. To gain proper mix design with great engineering properties and to obscure mechanical loss nano-silica powder was employed in mix combinations. The final results of compressive, flexural and splitting strength of mixtures tested after 28 days curing in laboratory were maximized with Taguchi method. Finally, the results reviled that the mix with 27% crumb rubber (by mix volume), 50% fly ash (by weight of cement) and 2% nano-silica (by weight of cement) incorporations, should be considered as optimal mix.